English:Hārūn al-Rashīd (also spelled Harun ar-Rashid, Haroun al-Rashid or Haroon al Rasheed; English: Aaron the Upright, Aaron the Just, or Aaron the Rightly-Guided; March 17, 763 – March 24, 809) was the fifth and most famous Abbasid Caliph. He ruled from 786 to 809, and his time was marked by scientific, cultural, and religious prosperity. Art and music also flourished significantly during his reign. His life and the fabulous court over which he held sway have been the subject of many tales: some are factual but most are believed to be fictitious. The famous The Book of One Thousand and One Nights contains many stories that feature a caliph carrying his name.